基于遥感数据的黄河口湿地变化研究

Research of Wetland Change in the Yellow River Estuary Region Based on Remote Sensing Data

基于1992-2015年12期黄河口地区Landsat TM/ETM数据,解译并分析了黄河口湿地的变化情况,以期为进一步识别湿地变化原因和开展湿地生态恢复等研究提供科学理论依据。研究结果表明:近24年来,黄河口湿地演变存在显著的空间异质性,在黄河口湿地总面积减少的背景下,各类湿地面积有增有减,部分湿地表现出破碎化的趋势特征;黄河口湿地以天然湿地为主,近24年来,天然湿地面积呈萎缩趋势,人工湿地面积呈扩张趋势,黄河口湿地总面积整体呈湿地退化和人工化趋势;天然湿地中,滩涂湿地面积最大,草甸湿地面积减少趋势最为明显,除河流湖泊湿地面积平缓上升外,其它各类天然湿地面积均呈下降趋势;人工湿地中,水库坑塘湿地和盐田及养殖池面积均呈上升趋势,其中盐田及养殖池面积表现出强烈的扩张趋势;黄河口湿地的变化是多年来气候变化、黄河水沙、人类活动等因素共同作用的结果,而驱动因素相对贡献的量化评定还有待于进一步探讨。

Based on the Landsat TM/ETM data in the Yellow River estuary region from 1992 to 2015,the changes of the Yellow River estuary wetlands were analyzed so as to further identify the reasons of wetland change and provide scientific theories for the wetland restoration. The results indicated that the Yellow River estuary wetland evolution showed significant spatial heterogeneity in recent 24 years. The total wetland area in the Yellow River estuary region decreased. Under this background,some types of wetland area increased and the others decreased,and some wetlands demonstrated a trend of fragmentation. Natural wetland was the main wetland type in the Yellow River estuary region. In recent 24 years,the natural wetland area showed a shrinking trend while the constructed wetland area showed an expanding trend. The total area of the Yellow River estuary wetland showed a trend of wetland degradation and artificialization. In the natural wetlands,the tidal wetland area was the largest; the decreasing trend of meadow wetland area was the most evident; apart from the river and lake wetland area which gently rose,other kinds of natural wetland area showed downward trends. In the constructed wetlands,the areas of reservoir and pond wetlands,salt ponds and culture ponds showed an upward trend,especially the salt ponds and culture ponds showed a strong expanding trend. The Yellow River estuary wetland change was the results of climate change,the Yellow River water and sediment and human activities for years. The assessment of relative contributions of the driving factors still needs further discussion.